Generation of Broadband Chaotic Laser Using Dual-Wavelength Optically Injected Fabry–Pérot Laser Diode With Optical Feedback

Enhancement of Chaotic Signal Bandwidth in VCSELs Induced by Polarized Optical Injection

“…One of the most important quantities for the applications of the optical chaos is the bandwidth of the chaos. Methods developed to enhance this bandwidth have focused on the use of single optical injection in VCSELs [19]- [21] or DFB [22], [23] subject to optical feedback, double optical injection in chaotic Fabry-Perot laser diodes [24] or VCSELs with a fiber ring resonator [25]. Very recently, Hong et al [19], [20] have experimentally developed several strategies to enhance the chaotic bandwidth: continuous wave (CW) or a chaotic beam unidirectionally injected into a chaotic slave VCSEL, a chaotic VCSEL unidirectionally and mutually coupled with a CW VCSEL, and a CW VCSEL coupled with another CW VCSEL.…”

Generation of flat-spectrum wideband chaos by fiber ring resonator

“…To be specific, it fluctuates within a range of only 61.5 dB with a standard deviation of 0.97 dB. Compared with the previous results, 14,17,19 ours are much flatter: not only are the high-frequency oscillations excited but also the low-frequency components are enhanced greatly; furthermore, the peak of relaxation oscillation is eliminated. The increase in amplitude of time series (see the left inset), recorded by the 4 GHz oscilloscope, definitely shows the low frequency energy enhancement.…”

“…[14][15][16][17][18] And still others show that dual injection from two external lasers can further enlarge it. 19,20 However, the schemes of the injection methods are complex and delicate, because two or three lasers should be matched in terms of multi parameters. Moreover, the dominant laser relaxation oscillation leads to a nonuniform power density distribution.…”

“…Moreover, the dominant laser relaxation oscillation leads to a nonuniform power density distribution. [14][15][16][17][18][19][20] Resultantly, the low energy in lowfrequency band (below the relaxation oscillation frequency) reduces the utilization efficiency of chaotic light because most electronic acquisition devices act like a low-pass filter. Although electro-optic or optoelectronic oscillators can generate flatter chaotic spectrum than optical injection method, 21-23 high-speed modulators and wideband electronic amplifiers are costly.…”

Impact of Chromatic Dispersion on the Performance of COTDR

“…The experimental setup is also displayed in Fig.3(a), where the bandwidth enhancement of the chaotic source was realized by using external optical injection (i.e., DFB2) [11], [12]. Figure 5(a) shows the RF spectrum of the bandwidth-enhanced chaotic light.…”